There are certainly times when a heavy weighting in favour of latency makes sense and times when it doesn't - and interactivity is the defining factor for me.

There are certainly times when a heavy weighting in favour of latency makes sense and times when it doesn't - and interactivity is the defining factor for me. If I'm synthesizing an FPGA core or rendering a video I don't want latency optimisation to slow it down if I've wandered away from the computer, and left it to do its thing. If, on the other hand, I want to get on with something else while the long-winded task is progressing, I want what I'm doing now to be have priority, to be regarded as the "foreground" task, and I don't mind if the long-winded process takes longer as a result (within reason!) And, crucially, if that long-winded task eats all the RAM and I decide to cancel it, I want the user-interface to remain responsive so I can do that. I'm glad you've recognised the delights of a low-latency interface. The ideal interface is invisible, unnoticed by the user - my own thoughts are that an unpredictable response time is jarring, causing the interface to be noticed in a way that it shouldn't be - I've heard it called "jank" in the context of cellphone apps. So I believe people do recognise it, but probably underestimate how much it detracts from a pleasant user experience.